yesterday I went to advance the timing a bit, set the leading, went to the trailing making sure it was all good and noticed that sometimes the timing would jump to the leading mark and then jump back and sometimes stick on the leading mark for a bit?
I checked the cap for trace marks but it's clean. When I swapped in the elec. dizzy I just used the coils from the car at the junkyard could the coil be going?

what's going on guys?

thanks,
matt

 

Are your plug wires arcing (usually near the coils)?

Smyonly guess.

 

Where did you attach the timing light's sensor clip? If it's a cheap one it can recieve signals from adjacent leaky plug wires. I had the exact same problem once.

 

Plug wires are good they are a set of accel custom fits. no arching at all and the timing light is a snap-on.
I connected the lead to the trailing wire of #1 rotor.

 

Jeff is right. Depending on which of my timing lights I use, I have the same thing happen. Actually my cheaper light doesnt pick up the stray signal, funny huh?

 

At first I thought I was having the same problem as the '80 ignitions where they both accidentally fire at the same time. Luckily, it was just leaky wires. Or maybe your sensor is too sensitive.

Try moving the sensor clip to different parts of the wires. Also put it on the coil to cap wires. It will produce twice as many strobes, and will light up TDC as well as the portion of the pulley 180º after (heh, kinda like DLIDFIS does on both Leading wires, hehe). It's never been a problem thus far.

 

You change the igniter with a good one? Sounds like a bad igniter.

 

Yeah, those clip on tining lights don't work well with rotaries. Haynes even mentions it. You need the cheap one that hooks between the plug and the wire. I borrowed my friends 150 dollar digital clip on once and the timing mark was all over the place. I went out and bought one for 20 bucks and it is dead on.

 

My cheap clip-on from Canadian Tire works excellent.

 

haven't check my post in a while... thanks for the responses guys. I'm hitting a yard tommorow which I recently discovered that has a grip of rx-7s
(hard to find in ventura county, ca).
I'll pick up a few ignitors and see if there is any change.. other wise I guess it's just the timing light.

How do I test the ignitor if it's anygood?

 

Haynes has a method to test the resistance, but it doesn't guarantee that it works. I can't remember what or how to test it though. Maybe someone else has the book handy.

 

Welp, I only got a chiltons so if anyone has the haynes manual, well you know

thanks,
matt

 

I got $8 in change once outta a single RX-7 at the auto wreckers.... I could make money just going there everyday...

Jeff

 

you know what man? im having the exact same problem. My trailing timing is missfiring like crazy. And the leading fires insted of the trailing sometimes. If you put new igniters on and it fixes it let us know. I've been reluctant to buy new igniters. So keep us posted!!!

 

got about 5 ignitors from the yard today for $5, hehe the guy running the yard thought they were just some connectors.


I'll try them out as soon as I figure out my 5 spd problems, as I rather have a smooth car then a loapy idle (I think it sounds cool anyway).

hehe, yeah the first thing I always do is look under the seats for change

matt